Replaceable wearing parts for crushers with tilting bowls



Oct. 6, 1964 J. B. BOND ETAL 3,151,817

REPLACEABLE WEARING PARTS FOR CRUSHERS WITH TILTING' BOWLS Filed May 1, 1961 2 Sheets-Sheet 1 1964 J. B. BOND ETAL 3,151,317

REPLACE ABLE WEARING PARTS FOR CRUSHERS WITH TILTING BOWLS Filed May 1, 1961 2 Sheets-Sheet 2 I JACK 5. 5mm M asai/e 8.6?1/[11/05? 22 3? 4r%er [far/er A United States Patent REPLACEABLE WEARING PARTS FOR CRUSHERS WITH TIL'I'IN G BOWLS Jack B. Bond, Hales Corners, and Oscar C. Gruender, Milwaukee, Wis., assignors to Nordberg Manufacturing Company, Milwaukee, Wis., a corporation of Wisconsin Filed May 1, 1961, Ser. No. 106,559 2 Claims. (Cl. 241290) The invention relates to an improvement in tilting plane structures for gyrating head crushers in which the bowl is releasable under overstress. It is illustrated in connection with a cone crusher of the general type shown in Patent No. 2,438,049, issued March 16, 1948.

One purpose is improved means for preventing abnormal wear on the inner conical surface of the tilting ring of such a crusher.

Another purpose is to prevent abnormal or adhesive wear on the opposed part of the frame of such a crusher.

Another purpose is replaceable wearing parts for the tilting plane structure where wear is, in practice, greatest.

This application is a continuation-in-part of our application Serial No. 47,856, filed in the United States Patent Office, August 5, 1960, now abandoned.

Other purposes will appear from time to time in the course of the specification and claims.

The invention is shown more or less diagrammatically in the accompanying drawings, wherein:

FIGURE 1 is a vertical axial section showing the opposite sides of a cone crusher to which the present invention has been applied;

FIGURE 2 is an enlarged section of a modified form of the opposed conic surfaces between the main frame and tilting ring in FIGURE 1; and

FIGURE 3 is a variation of FIGURE 2.

Referring to the drawings, 1 generally indicates a circumferential side frame member of the crusher. At the upper end of the frame is shown an outwardly extending flange 2 with an upward projection 3. The upper part of the frame and flange 2 and projection 3 are formed to provide a conic inner seating surface 4. Positioned above the frame is a bowl supporting or tilting ring 5. This ring is shown as interiorly screw-threaded as at 6 to receive the corresponding screw threads 7 of a bowl structure generally indicated at 8. The details of the bowl structure are not of themselves part of the present invention. It will be understood, however, that a conic head is gyrated within the bowl 7, the head and bowl defining together a crushing zone or space. The tilting ring is shown as having a conic surface 10 opposed to the conic surface 4 of the frame. When the parts are in normal position during normal crushing it will be understood that the ring 5 is seated upon the frame about its entire circumference, with the conic surfaces 4 and 10 abutting throughout the circumference of the machine. The conical surfaces match or have the same included angle so that they contact during normal operation throughout their length as well as circumference. The parts are held in such position by any suitable compression means, for example, the springs 15, which are compressed between any suitable bottom abutments 16 and the lower surface of the frame flange 2. Any suitable tension members 17, such as bolts or the like connect the abutments 16, preferably adjustably, to the tilting ring 5.

These tension members are shown as bolts provided with suitable nuts 18 but they might be otherwise. The bolts pass through suitable apertures in the frame flange 2. The gyrating head applies an ever-moving wave of rotary upthrust against the bowl during crushing. The upthrust wave may cause a minute movement of the tilting ring on the frame. If the tilting ring were free, it might slowly walk around the main frame, like a falling coin. To prevent this walk we use one or more dowels 19.

It will be understood that when uncrushable material is present in the crushing zone or space between head and bowl, the bowl is tilted upwardly away from the head. In the course of this upward tilting movement some part of the ring 5 is tilted upwardly away from the flange 2 or the projection 3 of the frame. As a result, at one side of the crusher, the rings 5 may be lifted somewhat. The maximum withdrawal will be determined by the location of the uncrushable material. Such uncrushable material may include tramp iron, such as dipper teeth and the like. When a large uncrushable mass enters the crushing zone and forces a local upward tilting of the ring 5 the springs 15 are compressed to a varying degree about the circumference of the machine. In practice, a difficult wear problem results.

Assume for example that tramp iron is passing through the right side of FIGURE 1. The right side will be up, although it is not shown that way. On the other side the wear occurs which would be at the left in FIGURE 1.

At the zone generally indicated at A, being diametrically opposite the tramp iron, the surface 4 and 10 will separate at the bottom but will remain in limited contact toward the top. In theory, we then have two identical cone frustums,'slightly separated on one side and in point contact on the other side. In reality, point contact is not achieved, nevertheless, the area of contact will be quite limited since the lower part of surfaces 4 and 10 on the left side will separate and the adjustment ring 5, at least initially, pivots about the upper portion of 4 and 10. At least momentarily, the majority of the spring thrust will be concentrated in a quite limited area between 4 and 10. Since the surfaces 4 and 10 are on an angle to the vertical and the spring thrust can be assumed to act vertically, the left side of the adjustment ring will slip a small amount. During such slippage, a good bit of the total spring thrust will be on the limited area of contact making the unit pressure extremely high, and the surfaces, if of a similar material, for example both of steel, will have a quite high coefiicient of friction resisting such slippage. Assuming a total spring force on the order of 300,000 lbs., for example, the effective force normal to the limited contact between surfaces 4 and 10, assuming they are at a 30 degree angle to the vertical, will be something like 350,000 lbs. When tilting occurs the forces are materially increased, and a part of this force would be concentrated on an area of a few square inches, at the most. The same thing occurs as they return to full contact, except slippage is in the other direction. Slippage between two similar surfaces under high pressure over a quite limited surface area, on a cyclical basis, will cause tremendous shear forces resulting in surface disintegration, heat generation and molecular fusion of the disintegrated particle.

From the action described above we obtain what might be referred to as a cyclical skid-welding. This means that repeated skidding or rubbing between the metal surfaces generates heat rising to a high temperature which eventually causes Welding between adjacent surfaces. The temperature of the surface goes above the melting temperature of the material. Welding is due to melting. Thus repeated skidding on a rapid cycle does not give the surfaces a chance to cool and the temperature will go above melting temperature. Further, once welding occurs and minute particles are torn from each surface, we have a point of concentration and thereafter the skidwelding builds up or snowballs.

Whatever the cause may be, large pieces of metal are gouged out or pulled out of the opposed surfaces and fused to each other. Such pieces, which may be roughly described as oyster-shaped, may include metal portions from both of the upper surfaces 4 and which are welded together by molecular fusion or compacted in some way. The fused portions eventually tear loose from not one but both surfaces leaving large pits or cavities. The result, from a practical sense, is disastrous. In a heavy duty crusher, particularly of large size, and under heavy load, this pitting or removal of metal slugs may end by seriously damaging the opposed conic contacting surfaces.

This abnormal wear in creating separated metal slugs changes the entire geometry of the crusher and upsets the dimensional relationship of the crushing cavity, thereby destroying its ability to accurately reduce material to any desired size. In short, the machine will no longer be accurate.

It is our belief that the situation is primarily caused by or at least made worse by the fact that the opposed parts are of the same metal component, steel. We find that the condition can be greatly ameliorated by applying covering elements or inserts to one or both of the opposed conic surfaces, which are either non-metallic or non-ferrous and different from the metal of the opposed surfaces. One of the advantages of using different materials in contact with each other, as in FIGURE 2, is that the surface will have :d ifferent.melti ng points. This means that as the temperature goes up, one surface will melt first. By the time the temperature gets up to the melting point of the other surface, the first surface gets out of the way, so to speak. Thus differential melting points prevent the skid-weld. Further, by using brass or bronze as the liner, we introduce a dirty surface, so to speak, which resists welding since bronze will oxidize and it is well known that it is diflicult to weld an oxidized surface. For example aluminum is extremely diflicult to weld because it rapidly oxidizes. In this respect, the use of aluminum bronze is advantageous.

To take, for example, FIGURE 2, we illustrate conic ring segments mounted on the conic surface 4 of the frame. Thesesegments may be of any desired length and number, but we find it advantageous to employ, say, three segments of about 120 degrees each. The segments may abut, edge to edge, but We find it advantageous to leave at least a slight space between adjacent segments.

The segments may be secured in place by various means. For example, we may weld, braze or bond along each edge as at 21'and 22 For the inserts, for example, we may employ bronze, or some bronze alloy or any suitable nonferrous metal. This is given as an example. It is also practical to hold the segments 20 in position on the surface 4, in recesses, with or without a bottom flange or positioning support. Instead of welding, they may also be pinned or doweled in position.

Whereas in FIGURE 2 we illustrate inserts only in the conic surface 4, it will be understood that such inserts may be applied, as well or instead, on or in the surface 10. In FIGURE 3 we illustrate such inserts at 30, the inserts being welded, brazed or otherwise bonded along each edge at 31 and 32. It will be understood, as shown in FIG- URE 3, that the inserts may be employed on either conic surface 4 or 10, or, if desired, on both.

In FIGURES 2 and 3 we have shown the inserts welded, bonded or otherwise mounted on the face of the surfaces 4 and 10, but they might be recessed into either or both surfaces, such as shown in FIGURE 1. The recess might be undercut or otherwise.

Whereas we have described the use of bronze or nonferrous liners or inserts, we also find it advantageous to employ inserts of non-metallic material.

For example, an epoxy resin may be applied and permitted to harden. The resin has a relatively longwearing life, and may easily be removed when worn. Optionally, the resin, which has high adhesive characteristics, may be allowed to adhere to the opposed metallic surfaces of the ring 5 or the frame, or both. Or, with the use of undercut recessing, the metallic walls may be treated with grease or some substance to prevent adhesion, and the resin may be held in place by its shape. It may then the more easily be removed when worn, since it is not permitted to adhere to the metal. We may use a fabricated product such as Sorbtex, presently obtainable from Voss Engineering, Inc., Chicago, Illinois. In this case, the material is a cotton or fabric impregnated with neoprene with a Mylar surface. We may as well use a self-lubricating plastic such as Teflon, for example. In fact, a large number of plastics will work, but something along the lines of Sorbtex is preferred since it has a hard wear-resistant surface of Mylar backed up by a tough but somewhat compressible and resilient body of neoprene impregnated fabric.

We realize that whereas we have shown a practical and operative device, and variations thereof, our description and drawings are to be taken as, in a broad sense, illustrative or diagrammatic. As above suggested, the inserts or removable or replaceable wearing parts may be applied to either or both of the conic surfaces.

They may be metallic or non-metallic, but it is important that the opposed surfaces are not of a metal, or combination ofmetals, which will fuse together or weld under heat and pressure, as may be the case with current use of cast iron or steel frames and tilting rings.

We claim:

1. For use in a gyratory crusher having a circumferential main frame with an outstanding supporting flange defining an upwardly and outwardly conical circumferential surface, a tilting ring being mounted on the outstanding flange and having an upwardly and outwardly conical circumferential surface corresponding to and adapted to oppose the upwardly and outwardly conical circumferential surface on the main frame, yielding means releasably holding the tilting ring on the main frame so that when the tilting ring tends to move up on one side due to an overload, such as tramp iron in the cavity, the surface on the opposite side of the tilting ring tends to slip on the opposed surface on the main frame under the pressure of the yielding means, and a circumferential removable lining between said opposed surfaces, the lining being of a non-ferrous material and having a melting point substantially lower than that of steel, to thereby resist adhesive fusion.

2. The structure of claim 1 further characterized in that the material of the lining is bronze.

References Cited in the file of this patent UNITED STATES PATENTS 1,691,553 Rumpel Nov. 13, 1928 1,717,894 Rumpel June 18, 1929 2,017,108 Symons Oct. 15, 1935 2,158,778 Rumpel May 16, 1939 2,553,987 Stevens May 22, 1951 2,555,064 Stevens May 29, 1951 2,875,955 Wendshu Mar. 3, 1959 2,970,775 Chapman Feb. 7, 1961 2,970,783 Cheyette Feb. 7, 1961 

1. FOR USE IN A GYROTORY CRUSHER HAVING A CIRCUMFERENTIAL MAIN FRAME WITH AN OUTSTANDING SUPPORTING FLANGE DEFINING AN UPWARDLY AND OUTWARDLY CONICAL CIRCUMFERENTIAL SURFACE, A TILTING RING BEING MOUNTED ON THE OUTSTANDING FLANGE AND HAVING AN UPWARDLY AND OUTWARDLY CONICAL CIRCUMFERENTIAL SURFACE CORRESPONDING TO AND ADAPTED TO OPPOSE THE UPWARDLY AND OUTWARDLY CONICAL CIRCUMFERENTIAL SURFACE ON THE MAIN FRAME, YIELDING MEANS RELEASABLY HOLDING THE TILTING RING ON THE MAIN FRAME SO THAT WHEN THE TILTING RING TENDS TO MOVE UP ON ONE SIDE DUE TO AN OVERLOAD, SUCH AS TRAMP IRON IN THE CAVITY, THE SURFACE ON THE OPPOSITE SIDE OF THE TILTING RING TENDS TO SLIP ON THE OPPOSED SURFACE ON THE MAIN FRAME UNDER THE PRESSURE OF THE YIELDING MEANS, AND A CIRCUMFERENTIAL REMOVABLE LINING BETWEEN SAID OPPOSED SURFACES, THE LINING BEING OF A NON-FERROUS MATERIAL AND HAVING A MELTING 